A union says nurses are deeply frustrated as a four-year fight for a gender pay equity agreement stalls again.
Nurses Organisation members had been set to vote on an agreement with the District Health Boards last month but some were unhappy it did not include the amount of backpay they were expecting.
Now the 40,000 members have voted to take it to the Employment Relations Authority instead.
Nurses Organisation chief executive Paul Goulter said it would also ask the authority to rule on two more problems that had emerged after talking to members - whether senior nurses are getting enough of an increase and how often gender pay will be reviewed.
Nurses felt the authority was the best place to settle the dispute and they wanted it done quickly, he said.
"The nurses are deeply frustrated - and I'm sure on the employers side that is the case as well," he said.
Spokesperson for the DHBs, Tairāwhiti DHB chief executive Jim Green, said it did not understand what had gone wrong because the union had agreed to wording in settlement in December.
That included lump sump payments to recognise the time taken to reach an agreement, and a process to make sure the gender pay gains are not eroded over time.
There would have to be mediation before any employment relations hearing, he said.
Nurses first started their fight for pay equity in 2018 - to address years of underpayment because they are a workforce made up predominantly of women.
A settlement appeared to have been reached late last year but problems emerged last month when some nurses noticed they were not getting backpaid to December 2019 as they had expected.
Health Minister Andrew Little has said if the union was successful, it could add hundreds of millions of dollars to the cost of the pay equity claim.
Goulter said only about 40 percent of nurses in New Zealand worked for DHBs and many more were waiting on the outcome of the dispute before making their own claims.
He told Morning Report the settlement was essentially a draft proposal and rejected claims it had been a legally-binding done deal.
"It quite simply wasn't the case. We were still negotiating what was essentially a draft proposal and then the legality of the backpay came up, so that stop that process happening," he said.
"It wasn't even a proposal capable of acceptance. The process of finalising it got upset by the question of the legality of the back pay, so it was never completed. There was never a settlement."
The union had been under the impression negotiations were ongoing and that the proposal was always a draft until the nurses voted on it.
There was no way the DHB would have thought otherwise too, he said.
"The employers, the DHBs would have to have the same position, because there was no a finalised terms of settlement.
"That's essentially the problem we've got now in that we've got three outstanding items. We disagree between us on that and that's why we're taking it off to the Authority for a determination. That's preordained in the Act, we're just following the processes in the Act."
He said the outstanding issues could amount to about $600 million to resolve.
"Everyone is just sick and tired of this dragging out and that's why it needs to be brought to a head and that's why it's going to go the Employment Relations Authority for a determination because that basically finishes it off," he said.
"Nurses are sick of it and want to get on with their jobs but they have a deep sense of injustice around gender discrimination."